A certification system would just be another cost a LAQ would have to endure and would eventually be passed on to the client. Quite honestly some LAQ have talent and sadly some do not. Not all are talented in all arenas. How would you go about cerifying someone who only does handguided as opposed to someone who only does Computer guided, someone who has a stitch regulator and someone who does not? I see no point in putting a regulation on a cottage industry thereby blocking someone who just barely has the funds to get the machine from entering the market.
Availability of funds does not equate skill, artistry and talent. So no, a certification process is not the answer, it is the maker of the top responsibility to ensure the LAQ they entrusted their top to does work that fits within THEIR (the piecers) standards, not some standard made up by a group of "professionals" in the industry.
I agree that communication is key. I have LA for several clients and only 2 have actually hand delivered the quilt to me and discussed options. Of those 2 only 1 actually picked up the quilt in person. I am honored by anyone who likes my work enough (based on photos) to entrust their tops to me. I want them to be confident in their decision that they entrusted their quilt to the right person. I want to make their quilt sing and be even more beautiful then when I received it. And I want my client to be over the moon happy with my work because I want them to recommend me to somebody else.
Reputation is everything to a LAQ so I really don't think a certification system is the answer.